Endocrine System Structure and Hormones — NEET Biology
📚 Practice ConceptThere are special chemicals which act as hormones and provide chemical coordination, integration and regulation in the human body. These hormones regulate metabolism, growth and development of our organs, the endocrine glands or certain cells. The endocrine system is composed of hypothalamus, pituitary and pineal, thyroid, adrenal, pancreas, parathyroid, thymus and gonads (testis and ovary). In addition to these, some other organs, e.g., gastrointestinal tract, kidney, heart etc., also produce hormones. The pituitary gland is divided into three major parts, which are called as pars distalis, pars intermedia and pars nervosa. Pars distalis produces six trophic hormones. Pars intermedia secretes
Which of the following statements about hormone-producing structures are correct? S1. Pituitary, thyroid, adrenal, pancreas, and gonads are examples of organised endocrine glands. S2. The gastrointestinal tract contains diffuse hormone-producing cells, distinct from classical endocrine glands. S3. Organs like the heart and kidney are not typically considered part of the endocrine system despite producing hormones. S4. A composite gland like the pancreas functions solely as an endocrine gland, secreting hormones. S5. The modern definition of hormones expands the scope beyond chemicals produced only by organised endocrine glands.
View solution & NCERT explanation
Correct answer: B — S1, S2 and S5 are correct
This question assesses the comprehensive understanding of various hormone-producing structures within the human body, as described in the NCERT text. S1. Pituitary, thyroid, adrenal, pancreas, and gonads are examples of organised endocrine glands. This statement is CORRECT. NCERT states: "Pituitary, pineal, thyroid, adrenal, pancreas, parathyroid, thymus and gonads... are the organised endocrine bodies in our body." S2. The gastrointestinal tract contains diffuse hormone-producing cells, distinct from classical endocrine glands. This statement is CORRECT. NCERT mentions: "Endocrine cells present in different parts of the gastro-intestinal tract secrete four major peptide hormones" and earlier refers to "diffused hormone-producing tissues/cells". S3. Organs like the heart and kidney are not typically considered part of the endocrine system despite producing hormones. This statement is NOT CORRECT. NCERT explicitly states: "In addition to these [organised glands], some other organs, e.g., gastrointestinal tract, liver, kidney, heart also produce hormones." This implies they are part of the broader endocrine system. S4. A composite gland like the pancreas functions solely as an endocrine gland, secreting hormones. This statement is NOT CORRECT. NCERT states: "Pancreas is a composite gland... which acts as both exocrine and endocrine gland." S5. The modern definition of hormones expands the scope beyond chemicals produced only by organised endocrine glands. This statement is CORRECT. NCERT mentions: "The new definition covers a number of new molecules in addition to the hormones secreted by the organised endocrine glands." Therefore, statements S1, S2, and S5 are correct. Option A is incorrect because S3 is false. Option C is incorrect because S3 and S4 are false. Option D is incorrect because S4 is false. Option B correctly identifies S1, S2, and S5 as the correct statements. Recap: The endocrine system includes organised glands, diffuse tissues, and other hormone-producing organs, and the modern definition of hormones is broad.
What does NCERT say about There are special chemicals?
Has this concept appeared in NEET?
Which chapter is this from?
Through deep analysis of NEET and NTA, 176 of the 180 ReNEET 2026 (June 21) questions were already in the MedicNEET question bank before the exam.
176/180MedicNEET's Biology question bank is built from the same NCERT lines NTA picks repeatedly. Not random MCQs — questions crafted exactly like NTA crafts them.